FUZZY LOGIC CONTROLLER FOR THREE-LEVEL SERIES ACTIVE POWER FILTER TO COMPENSATE VOLTAGE HARMONICS

Abstract

In this paper, the three-level inverter is used as a series active power filter to suppress harmonic voltage drawn from a nonlinear load. This filter acts as zero impedance for the fundamental frequency and as high resistor for harmonic frequencies. Most previously reported three-phase series active power filters are based on two-level inverters with conventional controllers requiring a complex and a complicated mathematical model. To overcome this problem a fuzzy logic controller is used and extended to a three level series active power filter.
This work presents principles of operation and design of a fuzzy logic controller algorithm to control the harmonic voltages. The viability of the proposed algorithm is validated with computer simulation. The obtained results showed that source voltage is sinusoidal and in phase with source current as well as a reduced total harmonic distortion.